frankgv

Hello all,

Just tinkering , waiting for spring, lol.

Does placing a carb spacer under an Edelbrock performer rpm intake have the same effect as putting an AIRGAP performer rpm intake on the engine, cooling the fuel mixture or is there more to it then that.

Current a 64 vette, 327, AFR180 alum. heads , 2:02/1:64 , HEI, mild comp. cam, roller lifters, hooker side exhaust, 5 speed Keisler with low 3:67 first, 3:08 gears with 5th gear 0:67 overdrive, do a lot of high way driving also.

do have edelbrock rpm performer with 6:70 Holley street avenger.

1/8 mile : 8.40 at 85 mph, street tires. ( spinning)

Can the airgap give better ET and MPH? I do have hood clearance with an open functional 67 style hood.

Any thought and your expertise input very much appreciated.
Also are dual quads mostly for looks only in this case.

Thanks,
Frank DeWinter frankgv@att.net

C-1 Generation 2

I did have an air gap on my 350/ L48, changed to solid lifter with 650 Holley spead bore. I couldn't tell any difference from the regular Edelbrock manifold I had prior, with performance or hot restarts.
Now I have a ZZ4 with factory intake and Quick Fuel sb carburetor and cured hot restart and performance issues with an aluminum heat shield.
http://www.summitracing.com/parts/mr...FZE0aQodUrYAjA
I used the same type shield on my wifes 2nd gen Z28 and also helped issues.

Avispa

Frank, the air gap manifold has runners that are separated from the manifold's cylinder head flange and valley cover by a thick open space underneath. Just putting a spacer under the carb won't even come close to getting the same result of keeping heat transfer to the incoming fuel/air mixture to a minimum. If you have the hood clearance, I'd use the air gap manifold.

6T5RUSH

frankgv,

Had to jump in here and comment on keeping the motor running in the heat of summer. Think it feels good talking about heat as we are expecting another -9 degrees tonight (probably gonna' hit -10). Just strictly from a cooling of the fuel in the heat of summer, this is what I did and it works very well:



MR GASKET heat shield kit



Heat shield b/4 cut for vacuum hard line<br/>



Installed



With slightly raised air cleaner (using a 65/66 big block hood



Car is warmed up...infrared gun reading front fuel bowl temp



Again, fully warmed up...infrared gun reading thermostat housing

This works!

Jim
In God We Trust!

Hitch

I have an RPM Performer intake and a 1" spacer and the top end performance is better but not extremely noticeable. It can't hurt and if you have the hood clearance with a BB what can it hurt?

Hitch

frankgv

Thanks, just noticing the air gap does not have the oil filler tube boss, kind of hate to loose my finned valve cocers.

frankgv

Thanks.

frankgv

Thanks, may give that a try also,

frankgv

Thanks, I may try that.

SS409

Nice looking motor Jim!

6T5RUSH

SS409,

Thanks for the kudoos. Taken 3 years ago, she does need some freshening up. But, as you know you're never really done with them.

This bloody car REALLY has got under my skin, LOL!



Jim
In God We Trust!

AZDoug

If you are creative, you can mod the airgap to accept a modified oil filler tube, it may take a welder that knows how to weld cast aluminum.

A 1" carb spacer will raise your useable RPM range about 500 RPM, if your cam and heads are up to it.

Doug

frankgv

.?

Thanks,so its more then just drilling / cutting a hole in the airgap at the right place to put the oil filler tube in ? I have the edelbrock performer rpm with a 2" spacer, just because I had one, and don't know if there will be a diff, at the track, runs ok on the street.

AZDoug

There isn't a lot of real estate on an airgap to work with for an oil filler tube.

I think you can fit one in behind the carb, not so much at the front.

I think you can get away with out welding, but you need a baffle under the oil fill tube if it is over the lifters, vs the very front stock location.

That baffle could probably be installed by drill and tapping some say 10-32 screw holes from the under side,a nd using a very good Loctite on the screws, spacing a flat baffle about 1/2 below the oil filler hole, eliminating any welding. I like welding the baffle in place as there aren't any screws to fall out.

Keep in mind, the oil fill tube has to be really well sealed where it meets the manifold, as that low spot on an airgap is a water trap, and you don't want water getting into the motor around the oil fill tube.



Doug

frankgv

Thanks Doug, I'll have to really rethink this.

vetrod62

Not all that hard to do. Here is one I removed to up the HP on my engine.